elisp.eclass: Use EAPI defaults where possible.

src_unpack: Call default instead of explicit unpack.
src_prepare: Call default, so that the PATCHES variable will be
respected in EAPIs 6 and 7.
src_install: Call einstalldocs in EAPIs where it is supported.

Drop unnecessary die statements, because helpers die by themselves
in all supported EAPIs.

Signed-off-by: Ulrich Müller <ulm@gentoo.org>

eclass/elisp.eclass

@@ -38,7 +38,8 @@
 # @DESCRIPTION:
 # Space separated list of patches to apply after unpacking the sources.
 # Patch files are searched for in the current working dir, WORKDIR, and
-# FILESDIR.
+# FILESDIR.  This variable is semi-deprecated, preferably use the
+# PATCHES array instead if the EAPI supports it.
 
 # @ECLASS-VARIABLE: ELISP_REMOVE
 # @DEFAULT_UNSET
@@ -59,12 +60,6 @@
 # Space separated list of Texinfo sources.  Respective GNU Info files
 # will be generated in src_compile() and installed in src_install().
 
-# @ECLASS-VARIABLE: DOCS
-# @DEFAULT_UNSET
-# @DESCRIPTION:
-# DOCS="blah.txt ChangeLog" is automatically used to install the given
-# files by dodoc in src_install().
-
 inherit elisp-common
 case ${EAPI:-0} in
 	4|5) inherit epatch ;;
@@ -101,7 +96,7 @@ elisp_pkg_setup() {
 # WORKDIR for packages distributed that way.
 
 elisp_src_unpack() {
-	[[ -n ${A} ]] && unpack ${A}
+	default
 	if [[ -f ${P}.el ]]; then
 		# the "simple elisp" case with a single *.el file in WORKDIR
 		mv ${P}.el ${PN}.el || die
@@ -132,10 +127,10 @@ elisp_src_prepare() {
 		esac
 	done
 
-	# apply any user patches
+	# apply PATCHES (if supported in EAPI), and any user patches
 	case ${EAPI} in
 		4|5) epatch_user ;;
-		*) eapply_user ;;
+		*) default ;;
 	esac
 
 	if [[ -n ${ELISP_REMOVE} ]]; then
@@ -177,11 +172,13 @@ elisp_src_install() {
 	if [[ -n ${ELISP_TEXINFO} ]]; then
 		set -- ${ELISP_TEXINFO}
 		set -- ${@##*/}
-		doinfo ${@/%.*/.info*} || die
-	fi
-	if [[ -n ${DOCS} ]]; then
-		dodoc ${DOCS} || die
+		doinfo ${@/%.*/.info*}
 	fi
+	# install documentation only when explicitly requested
+	case ${EAPI} in
+		4|5) [[ -n ${DOCS} ]] && dodoc ${DOCS} ;;
+		*) declare -p DOCS &>/dev/null && einstalldocs ;;
+	esac
 	if declare -f readme.gentoo_create_doc >/dev/null; then
 		readme.gentoo_create_doc
 	fi